macosx: increase maximum number of messages for the messages panel

This is needed to a complete log as some modules like mkv are very
verbose. The actual size is not so critical anymore as messages
are only arriving if the panel is open.

modules/gui/macosx/DebugMessageVisualizer.m

@@ -201,7 +201,7 @@ static VLCDebugMessageVisualizer *_sharedMainInstance = nil;
 
         [_msg_lock lock];
 
-        if ([_msg_arr count] > 600) {
+        if ([_msg_arr count] > 10000) {
             [_msg_arr removeObjectAtIndex: 0];
             [_msg_arr removeObjectAtIndex: 1];
         }